11131561 has 8 divisors (see below), whose sum is σ = 13065920. Its totient is φ = 9283248.

The previous prime is 11131559. The next prime is 11131567. The reversal of 11131561 is 16513111.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11131561 - 2¹ = 11131559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11131567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21231 + ... + 21748.

It is an arithmetic number, because the mean of its divisors is an integer number (1633240).

Almost surely, 2^11131561 is an apocalyptic number.

It is an amenable number.

11131561 is a deficient number, since it is larger than the sum of its proper divisors (1934359).

11131561 is an equidigital number, since it uses as much as digits as its factorization.

11131561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43023.

The product of its digits is 90, while the sum is 19.

The square root of 11131561 is about 3336.3994065459. The cubic root of 11131561 is about 223.2811310877.

Adding to 11131561 its reverse (16513111), we get a palindrome (27644672).

The spelling of 11131561 in words is "eleven million, one hundred thirty-one thousand, five hundred sixty-one".